In analog broadcasting, when changing to a new channel from a current channel, the video of the new channel is available immediately. In digital broadcasting, when changing to a new channel, output of video of the new channel is not immediately available; rather, there is a temporary delay before the video is available. A blank image is displayed during this delay until the video of the new channel is available. For this reason, viewers see a blank image while changing channels.
An interleaving scheme sometimes is used to enhance the reception rate in digital multimedia broadcasting (DMB) received by a moving receiver. In this case, the video delay caused by changing channels is longer due to the interleaving scheme.
If a digital broadcast receiver can simultaneously decode broadcasting signals of all broadcast channels, the video delay caused by changing channels can be prevented. However, practicality precludes manufacturing such a decoder.
Since such a video delay caused by changing channels results in viewer inconvenience, a scheme capable of eliminating the delay is desirable and needed.